Brake tester



Jan. 17, 1933. H. w. LANGBEIN BRAKE TES TER Filed June 25, 1930 Patented" Jan. 17, 1933 l UNITED SATA HAROLD w, LANGBEIiLor Los ANGELES, CALIFORNIA BRAKE I Application ied Ji1`n`e 23,

This inventionV relates to a mechanism for testing Vthe brakes of motorvehicles, and has as its primary object the'provision of a means whereby the brakes of a vehicle maybe test- 5 ed under varying vehicle load conditions.

Heretofore in the testing of brakes of 'Ino-l tor vehicles it has been'common practice to effect testing of theV brakes without regard to the fact that the brakes may vary in theirA efiiciency under variousvehicle loads. I have found in practice in testngthe brakes 'of motor vehicles that while the test may show the brakes as functioning properly with the vehicle empty or under la light load they will not be necessarily eficient when the vehicle is more heavilyloaded because under such load* ed conditions the vehicle frame Awill be `disposed in. closer relation to the vehicle'aXle than when under a light load and accordingly will eect a change in the'relation of the brake. gear carried by the vehicle frame and the brake operatingmechanism carried by the vehicle axle thereby resulting in a diierencein the action of the brake under the load condition. y

The present invention contemplates the provision of a vehicle brake testing mechanism embodying means whereby a conditionv of' various loads may be imposed on the vehicle body or frame during thebrake testing operation so as toenable determining of the effectiveness of they-brake under various load conditions ofthe vehicle.V

With the foregoing objects in view together with such other objects and advantages as may subsequently vappear the invention is carriedcinto eilect by the provision of a means for imposing various loads upon a vehicle frame adapted' to be operated in conjunction with a brake testing mechanism as will be hereinafter more fully described and claimed,

and'which is illustrated by way ofeXample in the accompanying'drawing, in which 1 Fig. 1 is a viewgin side elevation illustrat- F ing the application of the invention; f

Fig; 2 is a View in section and elevation asv seen on the line .f2-2 of Fig. 1 in thel direc- 'tion indicated bythe arrow`s Referring to the drawing more specifically A indicates 'a vehicle frame supported by irl-:s PATENT OFFICE TESTER 1930., serial yNo. 463,194."v i

springs B and C on the front and rear axles D and E, respectively, which are fitted with front wheels F and rear wheels G inthe usual manner, and which Iwheels are equipped with conventional brake mechanism indicated generally at H.

A brake testing mechanism is indicated generally Vat I and is here shown asl embody` ing a pair of rollers 3 and 4 arranged to afford a supportfor each of the brake carry- 6o ing wheels of the vehicle. The rollers 3 and 4 are operatively connected to brake testing indicators'in the usual manner, whereby on rotation of the vehicle wheels supported thereon and the application of the brakes therv effectiveness voi" thev brakes .may Vbe deterf mined. j

In the application of the invention as here shown manually controlledviiuid'pressure operated means are provided for imposing various loads on the vehicle frame when the vehide Wheels are Supported' OH the rollers 3" and 4 of thev brake tester, wherebythe brakes may betested under various vehicle load con ditions. This means is here shown as embodying a cylinder 5 in which is mounted for verticaly reciprocal movement a* piston 6 carried on a piston rod 7 projecting vthrough a packing gland8 konl the upper end of the cylinder 5;., 8'0' thel cylinder being disposed in a pit above which the vehicleu is positioned vwhen the wheels thereof'are carried on the rollers 3 andv 4 of the brake tester. f Means are provided for' effecting lconnec- 85 tion between the upper end of thev piston rod Z and the vehicle frame A, or to the vehicle body, which may be of any suitable construction but is here shown as comprising a flexible line IOwhich may comprise a chain or cable, 904 which lineisslidably connectedintermediate its ends/to a hookfor loop 11 formed on the vupper end ofthe piston 7 and the ends of which line are connected to hooks'12 and 13 adapted to be connected to the' sidemem'bers. 95 14v and 15 of the vehicle frame, the hooks being' here shown as attached to a bar 16 the ends of Vwhich are' extended into-channels formed in the frame' members, It is mani? I fest thatYV theconnection between the piston and the vehicle may be made at any conven ient point on the vehicle according to the construction of the latter, and therefor the means here shown for this purpose is merely illustrative. The cylinder is positioned so that its axis and that of the piston rod 7 will ex-V tend on a vertical plane leading intermediate the side frames ofthe vehicle. so that on 22 formed with passages 23 and AZirarranged4 to effect communication between either 4 of the conduits 17 and 18 and a source of fluid pressure supply through a conduit25 orto' Yeffect communication between the conduits 17 i and18 andan exhaust port 26 according to the position of the valveQQ. The valve is fitted with a hand lever 27 whereby'it may be .Clisposed in the desired position to effect delivery of fluid pressure to either sideof thepiston 6. They conduit 17 isA fitted with a pressure gauge 28'for indicating the pressure des` liveredtothe upper side of the piston 6 under Vwhich the latter is forced downwardly.

In the operation of the invention a vehicle is positioned with. the brake carrying wheels thereof on the rollers 3' and 4 of the brake tester 1 inthe usual mannerrwhereupon connection is effected between the vehicle frame and the piston rod 7 with the piston disposed in its uppermost position; the .piston being elevated by, effecting communication between the conduit 18 and the pressure supply conduit 25 4through the passage 24 of the valve,

22. AThewheels of thevvehicle vare then lset in operation in the usual manner to Veffect ac'- tuation of a. suitable indicator through one ofthe rollers 3 ork i as is common in brake testing operations. When it is desired to `eji'ect 'testing of the brakesfunder various vehicle load conditions the valve 22 is disposed to direct fluid pressure above the piston 6 thereby forcing the latter downwardly and imparting a downward pull on the vehicle frame. Y Any desired load may be thus im posed on the vehicle frame within limits and the extent of such load maybe determined by reading ofthefindicator 28. Y

' It will now be seen that the brakesy of the vehicle maybe testedV under various vehicle i. loads. l

After effecting the desired operations, the valve 22 is turned to open the upper end of the ycylinder 5 .to exhaust and to'direct fluid pressurev beneath the pistonf, thereby effect:l

ing restoration of the piston to its uppermost t position whereupon the connection between the piston rod and the vehicle frame may be detached.

It is to be understood that the manner ofV carrying the invention into eect is herein specifically set forth to enable those skilled in theA art to make and usey the same and is to be considered.as'illustrative and not inV av limiting sense; and that various changes may bemadefinthe parts and in their constructio'nand arrangement within the meaning of Y f the terms and scope of the appended claims without departing from the spirit of the invention. iv i' l For example, while the invention is shown as applied to the testing of brakes on the rear wheels of the vehicle, it manifestly may jbe employed in testingfbrakes on thel front wheels thereof, whichis eected in like inan-v ner, eitherjcoincident withthe testing ofthe brakes onthe rear wheelsl or independently theref., Furthermorejwhile theinvention isl l here shown. as appliedfto a brake testerembodying rollers'on which the" vehicle wheels are supported, it obviously may be employed with brake testers having other means, of vehicle wheel support. l claim: Y .7" p

1. In a vvehicle-brake testing Vmechanism,

theV combination with the vehicle wheel' su'p-, ports of a brake tester, of meansfor imposing various loads on the frame iof'a vehicle Y while the wheels thereof are carriedV on said of such imposed loads. i

supports and means for measuring the extent i 2' I ai mechamsm for testgthe brakes of a motor vehicle the combination with the rollers` vof a brake tester on which the wheels of Va vehicle areV adapted to be supported, manually controlled means forv imposing various loadson the frame of a vehicle while the wheels'fthereof are supported on *said rollers and meansfor measuring the extent offsuch imposed loads i 3. In a mechanism for testing the brakes of ay motory vehicle the combination with the rollers of a braketes'terA onwhich the wheels of a vvehicle are adapted to'be supported, means engageable with the frame of'a vehicle Vfor imposing various loads thereon while` testing the brakes thereof and means for measuring the extent of such imposed loads.

Il. In a mechanism ,for ytesting the'brakesv of a motory vehicle,'the combination with the wheel supporting rollersvof vehicle-brake tester, of manually controlled fluid pressure actuated means for creating various vehicle load conditions on the vehicle while. wheels thereof are supported on the rollers. Y,

5. ln the ,mechanismfor te tmV the brakes of a motor vehicletheA combinationv with the wheel supporting rollers of .vehicle-brake f tester, a cylinder, a piston reciprocably Ymounted. in.` said cylinder, :meansfor :effecting connection between said piston and a motor vehicle, means for directing fluid under pressure in the said cylinder for actuating said piston to thereby impose a load on the vehicle while wheels thereof are sup-'- ported on the rollers, and means lfor indicate ing the extent of such load.

6. In a mechanism for testing the brakes of a motor Vehicle, a brake tester including Wheel supporting rollers arranged to carry the wheels of a vehicle in eiiecting testing of the vehicle brakes, a cylinder, a reciprocal piston in said cylinder, manually controlled means for effecting reciprocation of said piston under fluid pressure, and means affording connection between saidpiston and a Vehicle arranged to exert a downward pull on the vehicle relatively to the Vehicle wheel supports of the brake tester.

7. In a vehicle-brake testing mechanism, the combination with a brake tester, of means for imposing various loads on thevehicle, and means for measuring the extent of such imposed loads.

8. In a mechanism for .testing the brakes of a motor Vehicle, the combination withl Wheel supporting members of ya Vehicle brake tester, a manually controlled fluid pressure actuated means :for creatngvvarious Vehicle load conditions on the Vehicle while wheels thereof are supported on the rollers, and

means for measuring the extent of such loads.

HAROLD W. LANGBEIN. 

